And with the likes of Ross Byrne putting in a huge shift at outhalf and former Irish U-20s Tom Daly and Hugo Keenan making their debuts, Cullen will head into the November break safe in the knowledge that he has some superb talent coming through. The emphatic victory, by five tries to one, also maintains Leinster's 100pc record over the hapless Italians as they secured their ninth win over Zebre in the rain at Stadio Sergio Lanfranchi in Parma.

Byrne, who scored last weekend in the win over champions Connacht, had crossed for three tries in his previous five appearances - but the 22-year-old doubled that tally in a fine display.

Zebre have been indifferent so far this season but Leinster knew they were facing a side with plenty of confidence after a first ever win in Scotland last weekend when they shocked Edinburgh 19-14 for their maiden victory of the season.

The wet conditions made it difficult for both sides but the task facing Leinster increased with lock Mike McCarthy being binned before Zebre hit the front when Italian international Dries van Schalkwyk got in after a good drive, with Carlo Canna converting.

Leinster refused to panic and Irish sevens captain Tom Daly crowned his debut with a try after a superb chip by impressive outhalf Ross Byrne.

Canna edged Zebre back in front with a 29th-minute penalty but Leinster led 12-10 at the break, with Daly this time the provider with a fine break which finished with him putting his housemate Byrne over for the first of his three tries.

Leinster effectively wrapped up the issue in the third quarter. Scrumhalf Jamison Gibson-Park put Byrne in for his second try after the Leinster pack had made the hard yards, with Isa Nacewa getting his second conversion to push last year's runners-up 19-10 in front. Ross Byrne continued to shine at No 10 and the bonus point was secured with Daly, Adam Byrne and Gibson-Park combined for Jack Conan to score after 57 minutes, with Nacewa again converting for 26-10.

Irish U-20 Hugo Keenan came on to make his senior debut for Leinster as Cullen's understrength side moved back on top of the table. Byrne completed his hat-trick 16 minutes from time after a pinpoint cross-kick from Ross Byrne again split the home defence and the Kildare native raced in to touch down.

Leinster head coach Leo Cullen. Photo: Matteo Ciambelli/INPHO

Nacewa landed his fourth conversion of the night before making way for Keenan to make his bow.